slow fading LED using a 555 timer.

Thread Starter


Joined Sep 23, 2018
Part of the problem may be the gain of the transistor. We've done something extremely similar here.

You must use two separate transistors, and not one darlington. This is because the darlingtons have a built in resistor that we can't use between base emitter.

A TLC should work, but the 1/3 and 2/3 points aren't quite as precision.

The gain of the transistor controls the loading in a key point of the oscillator. The difference between one transistor and two is a gain of 150 (one transistor) is about 18KΩ loading and a gain of 22500 (two transistors) is about 2.7MΩ loading.
I have a SciFi spaceship I want to accentuate but need 4 LEDs in different place but can all fade up and down together. What alteration to the schematic would be needed?
Thank You